POP3 (commonly referred to as just "POP") and IMAP (Internet Message Access Protocol) are mail protocols - they provide means to receive email on a mail client like Outlook, Thunderbird, Apple Mail, or even on your smartphone or tablet.
The Differences between IMAP and POP.
- IMAP allows users to store their email on remote servers.
- This two-way protocol also allows the user to synchronize their email among multiple devices, which is extremely important today when most people have at least two devices - their laptop, smartphone, and tablet.
- It allows you to read emails as they appear on the hosting server.
- All messages and any changes you make (delete, reply, forward, move) are seen by all mail clients configured with IMAP and will look exactly the same on webmail
It is commonly used for:
- Connect to the same email account from multiple mail clients (e.g. computer, smartphone, tablet).
- Provide access to multiple users to the same email account.
- Ensure all messages, including sent messages and message folders, are saved on the server.
POP downloads copies of your email messages to your mail client. Any changes you make (e.g. moving to a subfolder, deleting, etc.) will NOT be visible to other mail clients accessing the email account since you are only making changes to local copies. Most mail clients will give you options to keep messages on the server (instead of deleting them) after you've downloaded in the event you want to download the email into another email client.
It is commonly used to:
- Keep a backup of all messages.
- Archive permanent copies of messages.
- Download messages to a mail client to free up storage on the mail server.